Telephone system.



A. E. LUNDELL;

TELEPHONE'SYSTEM.

APPLICATION FILED OCT. 6. 1915.

1,272,280.. Patented July 9. 1918.

UNITED STATES PATENT oEEioE.

ALBEN E. LUNDELL, OF NEW YORK, N. Y., AssIGNoR To WESTERN ELECTRIC COMPANY, INCORPORATED, OF NEW YORK, N. Y., A CORPORATION OF NEW YORK.

TELEPHONE SYSTEM.

change systems in which means are provided for conveying a signal to an operator for indicating the designation of a calling subscribers line. 7

For this purpose it has been proposed to provide a normally idle controlling apparatus individual to an operators position, or a constantly moving apparatus common to a plurality of operators positions for controlling at the operators position signals designating calling lines.

The drawback of such arrangements is that if one controlling apparatus is provided for each position, a large number of such apparatuses have to be provided for a telephone exchange system, and if a constantly operating common apparatus is provided, such apparatus will be subject to severe, and to a certain extent unnecessary use, and furthermore, requires the consumption of much current.

According to one feature of the present invention, means, such as a controlling apparatus of the sequence switch type, is provided in common to a plurality of operators" positions for controlling the actuation of any one of a plurality of line lndlcating signals, said controlling apparatus having a normal position in which it rests when not in use.

According to another feature of the present invention, a controlling apparatus such as a sequence switch producing a definite number of operations, such as the opening or closure of an electrical circuit, during one complete movement, is provided with means for causing the production ofa definite number of operations, no matter in what position said sequence switch is required to produce said definite number of operations.

In other words, a sequence switch adapted to open twice an electrical circuit while moving from its normal position into its last position, said circuit changes being produced, for instance, in positions 4% and 12% Patented July 9, 1918.

Application filed October 6, 1916. Serial N 0. 124,066.

of said sequence switch, will cause two elec trical changes in the circuit even if it is operated to produce the first change when moving through position 12. This is attained by causing said sequence switch to perform always two rotations when called into service, thus making sure that one rotation will be complete. If the sequence switch is taken into use when standing in its normal position, the circuit interruptions produced during its second'rotation will be of no effect.

In another aspect, this invention may be defined as providing a controlling apparatus having a. definite normal position and adapted to produce a definite number of operations, such as circuit interruptions or closures, and may be used for producing these operations even if it does not stop in its normal or resting position.

The drawing shows a telephone station and an operators position to which such subscribers station may be connected, and an indicating arrangement devised in accordance with the present invention.

A sequence switch 17 may be of the structure described in Patent No. 1,127,808. This sequence switch has eighteen positions andcontrols in its various positions the closing and opening of the sequence switch contacts diagrammatically shown in the drawings. A master contact 18, which is closed in all positions except 1, controls the movement of the sequence switch toward position 1 after the switch has been moved outof this position.

Sequence switch 17 is common to a plu rality of operators positions (only two operators telephone'sets, 2 and 2, are shown) and controls the actuation of lamps 41, 26 or 47, provided at each operators position, and designating the number or class of the calling subscribers line.

A conductor 16 is connected in multiple to the left-hand back contact of a relay l5 and to the contacts of similar relays (notshown), one provided at each operators po sition.

No means are disclosed for extending a calling line to an operators position, as this does not affect the present invention. This means may be either automatic, such as a line finding or trunk finding switch, or manual, such as a plug and jack. All the subscribers lines belonging to one class or sequence switch contact 4. Similarly, all the other subscribers lines belonging to other.

classes are represented by connections to sequence switch contacts tOand 45, respectively. Conductor 19, individual tosubscribers line A, may be connected by the above. mentioned automatic or manual means to a conductor (S'leading to a contact of a listening key 3 of operators position No. 2, or to a conductor 6 leading to a contact of the listening key of operators position No. 2".

Another subscri-bers line B, belonging to a group of'lines, other-than line A, may also be associated with operatorspositions. 2 or 2 and a conductor 19, individual to line B,- may be connected to conductors 6"or 6-.

The subscriber at station 1, desiring, to obtain a. connection with an operators position- No. 2', removes his receiver fromthe-switchhook and causes, in the well-known manner, the extension of his line A to a trunk or cord circuit C, and the extension ofconductor 19 to conductor 6. The operator thereupon depresses her listening key 3, thus connecting her telephone head set to the calling subscribers line.

Assuming that sequence switch 17 is-standing in position 1, upon the actuation of the listening key 3, a circuit is closed from ground through a sequence switch contact 4L, a resistance lamp 5, conductor 6, a key contact 7, and the winding of a relay 8, to grounded battery. Relay 8 closes a circuit from ground, through its armature and front contact, the Winding of a relay 9, conductors 10 and 11, and a key contact 12, to

grounded battery. Relay 9 becomes energized and locks up its winding through its left-hand armature and contact 13. Relay,

9 also closes a circuit from ground through its left-hand armature, contact 14, the lefthand armature and back contactof a relay.

15, a contact 16 and the power magnet'of sequence switch 17, to grounded battery] The sequence switch is moved out of position 1, and under the control of its master'contact 18 from position to position, until'its circuit is broken in position 1.

While the sequence switch is moving from position 1 to 4:, the above-traced circuit, including lamp 5' and relay 8, is closed 'at sequence switch 4. As soon, however, as the sequence switch leaves posit-ion 4,. and until it reaches position 5,sequenceswitchcontact 4 is open, resulting in the deenerglzation of relay 8. Relay 9being locked-up, a circuit.

is closed from ground, through the armature and back contact'of relay 8, the right-hand front contact and armature vofyrelay 9, thev armature and back contactof relay 20, the winding-of relay 21, conductors 10 andgll, and key contact 12 to grounded battery. Relay 21 pulls up and closes a locking'circuit' for itself through its left-hand front contact and armature.

When the sequence. switchreaches position, 5, thejrelay 8 again becomes-energized. As soon as the sequence switclireaches position 6 and. until it moves out of position 13, a

circuit is closed from ground through a sequence switch contact 22, the winding ofrelay 20, and key contact 23, to grounded battery. Relay20 becomes energized. As soon as the sequence switch moves out of position 12 and until it reaches position 13, the circuit, including lamp 5 andrelay 8, is again opened. Upon the deenergization ofrelay 8, a circuit'is closed from ground'through. thearmature" and back contact of relay 8, the right-hand front contact andarmature ofrelay 9, the armature and front contact of relay 20, the .win'din'g of a relay 24, conductor=11and key contact 12, to grounded battery. Relay 24: pulls up and closes a locking circuit'for itselfat its left-hand front'contact'and armature. Relays 21'and- 24 being energized, a circuit is closed from grounded battery, through the right-hand armature and, a contact 25 of relay 21, lamp 26, the right-hand front contact andarmature of relay 24, and thehigh resistance right-hand winding of a relay 27, to ground. Relay 27 becomes energized, but lamp 26, which designates the-class of subscriber 1, does not become lighted while in series with the high resistance winding-ofirelay 27;

As soon as sequence switch 17 reaches position 18, a circuit is'closed'from grounded battery, through a sequence switch contact 28, the armature and frontcontact of-relay 27, and the left-hand winding'of a relay 29, to round. Rela 29 pulls up 'and closes a lockingv circuit fhr itself extending from ground through its right-hand front, contact, armature and winding, conductors 10 andll, and key contact 12, to grounded battery.

Sequence switch 17 then moves into position 1 and due tothe fact that theleft-hand back contact ofxrelay 15is still closed," the sequence switch continues When'it again: reaches position 17 a circuit is closed from grounded battery, through sequence switch contact 30, the left-hand armature and front contact of relay 29, and

the left-hand winding of relay 15 to ground.

Relay 15, by attracting its right-hand armature, closes a locking, circuit for itself through conductors l0 and 11, and by attracting its left-hand armature, opens the driving' circuit for sequence switch 17,

whereby'this switch after it has been moved by its 'master contact l8into-position 1, will be'stopped'. 7

Due to the attraction of the left-hand armature of relay-15, a circuit is closed from.

ground through the lefthand armature and contact 140f relay 9, the left-hand armature its rotation.-

and frontcontact of relay 15,-the low re-- ;contac-t 12 is opened, resulting in the unlockingof relays 15, 29, 9,21 and 24, whereupon lamp 26 is extinguished and the apparatus is ready for use in connection with another call.

The purpose of causing the sequence switch 17 to complete two revolutions for controlling the lighting of a class of service indicating lamp, is to insure the proper operation of relays 20, 21 and 24 in whatever position the sequence switch 17 may be when the operator depresses listeningkey 3.

Assume that sequence switch 17 is moving through position 12 when the operator depresses listening key 3. Relay 8 becomes energized and causes the energization and locking up of relay 9 in the-manner above described. When sequence switch 17 moves from position 12 to position 13, 2'. (2., in position 12%, the sequence switch opens the circuit of relay 8, and this relay in turn causes the energization of relay 24, relay 20 being energized at this time. In position 13 of the sequence switch, relay 8 again becomes energized over its original energizing circuit, and if the sequence switch would not be caused to. complete a second revolution, relay 21-would not become energized in response to the initiation of this call, because,as above described, this relay operates in position 4. of the sequence switch. For this reason, instead .of lamp 26, lamp 41 would be connected in circuit and thus a wrong class of service indication would be given to the operator. However, as described in connection withthe above assumed case, due to the provision of sequence switch contacts 28 and 30 and relay 29, the sequence-switch is caused to complete another revolution. 'When, during this second rotation, the sequence switch leaves position 4, relay 8 would again become deenergized, and would cause the operation of relay'21. In position 12 of the sequence switch, relay 24 will not be affected, due to the fact that it has already been locked up. Relay 15 cannot become energized in position 17 of the sequence switch when this sequence switch performs its first rotation, because relay 29 is not energized at that time- During the second revolution of'the sequence'switch, relay 15 will be energized in the above described manner and will cause the stopping of the sequence switch in position 1. Relays 21 and 24 being energized, lamp 26 will be lighted.

If aeallis initiated on line B, then also &

upon the actuation of. the listening key 3, relay 8 becomes energized. This relay stays energized until the sequence switch leaves position 12. Relays 9 and 20, having been energized and locked up in the meantime, while sequence switch 17 is moving from position 12 to position 13, relay 8 becomes deenergized and a circuit is established from ground, through the armature and back contact of relay 8, the right-hand armature and front contact of relay 9, the armature and front contact of relay 20, the winding of relay 24, conductor 11, and key contact 12 to grounded battery.

In position 13 of the sequence switch relay 8 again becomes energized. At this time a circuit is closed from grounded battery, through the right-hand armature and back contact of relay 21, a lamp 41 indicating the class of line B, the right-hand armature and front contact of relay 24, and the higln resistance right-hand winding of relay 27 to ground. Relay 27 becomes energized, but lamp 41 will not light up in series with this high resistance winding. Relay 8 will be maintained energized while the sequence switch is moving from position 13 to position 1. When the sequence switch reaches position 18, the circuit of relay 29 is completed and this relay locks up, and when during its second revolution the Sequence switch reaches position 17, the circuit of relay 15 is completed and this relay also looks up. Upon the opening of the lefthand front contact of relay 15, the driving circuit of the sequence switch is opened and this switch is stopped in position 1.

Due to the closure of the left-hand front contact of relay 15, the circuit for lighting lamp 41 is completed through the low resistance winding of relay 27. The operator, noticing lamp 41 lighted, will know the class of the subscriber calling.

Supposing that a subscriber of a class to which sequence switch contact 45 is individual is calling, relay 8 will become energized upon the depression of the listening key, and causes in turn the energization of relay 9. The driving circuit of the sequence switch 17 is then closed. While the sequence switch is moving from position 1 to position 4, relay 8 is maintained energized. As soon as the sequence switch leaves position 4, relay 8 becomes deenergized and closes a circuit forrelay 21, relay 20 being deenergized at this time. Relay 21 looks up its winding and closes a circuit from grounded battery, through its contact 46, a lamp 47, characteristic of this class of subscribers, the right-hand back contact and armature of relay 24, and right-hand high resistance winding of relay 27, to ground. Relay 27 becomes energized but lamp 47 does not light up while in series with the high resistance winding of this relay. Relay 8, being mainswitching device" common to the signaling means of said lines, and means 'con-trol'ledibysaid switching. device for simultaneouslycontrolling the actuatioirof a plurality of said signaling means in a manner characteristic for a plurality of callingzlines,

, 2. In a telephone exchange system, a plurality of lines, a plurality of trunks,ichar acteristic signaling means for each line at each trunk, a normally resting switchingda vice common to said trunks, means for eX- tending any one of said lineswhencallingc to any one of said trunks, and meanspperative thereupon and controlled by. said switch mg device for simultaneously actuating-at each trunk to which a calling line has been" extended the signalingmeanscharacteristic for the extended callingglines.

3. In a telephone exchange system, a plurality of lines Ofd'lffGTGl'lb classes, a-plural+ 'ity of trunks, a plurality ofoperators telephone'sets, means operative upon the initiation of a call on any one of said lines for eX-' tending it to any oneof-said trunks, alisteni'ng key for each operators telephone set, an electrical circuit closed upon the actua- 1 tion of any one. of said listeningkeys,--:aswitch normally at rest for controlling said circuit, means responsive to theactuatlon of anyone of said listening keys for-starting v the operation of said switch, and meansdepending 011 the class of the line calling. for causing said switch to change the electrical condition of said circuit in a predetermined manner.

4:. In a telephone exchange sy'stem, aplurality of lines, a plurality of operators" positions, means for extending any one of said lines to any one of said positions, aplurality of signals one for each of said lines at each, of said operators positions, and means nor mally at rest and common to said-operatorspositions for simultaneously controlling the actuation of said signals.

5. In a telephone exchange-system, a plurality of lines, a plurality ofoperatorspm sitions, means for extendingany one of said lines to any one of said operators positions, a plurality of'signals one *TEOI'VBQCII lineat said operatorspositions, means normally at rest and common-to saidopjer ators positions,

and means responsive to the-extension of calling lines to -'operators pos'itions' to-"oper' ate said second mentioned means to 'sii'nul taneouslv control" the actuation of the sig' nals individual to theca-lling'linesi 6.- In a telephone exchange system',-a"plurality o'f-lines, a plurality of'operator's tele; phone sets, a listenin'g key for cachet-said sets "for connecting?- it:' into telephonic association with acalling'line, a pluralityof s'ig nals'at each ofit said operators" positionsg one" signal beingindividual to' each line, a'- switch common to said operators positions and normally at rest, and means responsive fto the actuationof the listening keys 'at all of said operators positions for causing said switch to actuate at'each' position the ign individual to the callingi'line extended tothe position.

7 In combination, an electrical'circuit, "'a='185' switch having a normal and a pli'ira'lity'- of operatingpositions, means actuated 'in certain operatingapositions of said'switch 'for changing the electrical condition of said circuit, and means operable-in any position of said switch foncau'sing itto pro'dncesaid circuit changes; I

8. In: combination, an electrical 'circuit,".aswitch having=a 'normaland'a plurality of operating; positions, means for causing said-- switch tochange the electrical condition of said circuit a predetermined numberi oftimeswhile'moving from itsnormal position" throughallits operating positions"intoits normal position, and means-for causing'said 106 switch to produce said predetermined 'num her ozt'circuit ch'amges in whatever position itis caused to produce the'first circuit: change.

9'. In combination, an-electricalcircuit, V switch havinga normal and apluralitytxofi operating-positions, air actuating'niaghet for said switch, an energizing circuit-for said magnet, means efi'ective only; when said switch islin, its normal position*forclosingillio saidenergizing circuit, means 'operated=*i1r= certain operatingpositions of sai-dvswitcliz' for producing a change in said electricalcircuit, said changes being-ofapredeten" mined number, and-means-for'causing saidswitch to produce said" predetermined number of changes in the circuit if the Jenergiz? ing circuit is closed while the switch is. travelingith'roughany of its operating positionsi 10. In com'bination, a-pluralityof electri- 12o caldcircuits, a switch having anorma'l anda plurality of operatingpositions, an actuating magnet for said switch, an: energizing circuit for said magnet-having. a plurality of branchesone-branch being'provided -for each electrical circuit, a-circuit closingrfie-r vice in each of said branches, a contact in;

a common portion of saidenergiziing? cir cuit closed only in the-normal position of said i switch, means" operative upon" the "actuation of any one of said circuit closing devices and said contact for maintaining said magnet energized until the switch has moved through its operating positions into its normal position, means actuated in certain positions of said switch for producing changes in one of said electrical circuits, means operative in certain other positions ofsaid switch for producing changes in another one of said electrical circuits, and means for making said last two mentioned means eifective during one complete movement of said switch.

11. In combination, a plurality of electrical circuits, a switching device normally at rest, means for operating said switching device to simultaneously produce changes in said circuits at varying intervals, a signaling device responsive to said circuit changes associated with each of said circuits, and means associated with each of said circuits for determining the number of the effective changes to be produced in the circuit.

12. In combination, an electrical circuit, a rotatable switching device normally at rest, means operable during each complete rotation of said switching device for producing a certain number of changes in said electrical circuit, a responsive device controlled in accordance with the changes produced in said circuit, automatic means for causing a started switching device to complete two revolutions, and means for making the circuit changes produced during the second revolution of said device ineffective.

13. In combination, an electrical circuit,

a rotatable switching device normally at rest, means operable during each complete rotation of said switching device for producing changes of a certain character in said electrical circuit, a responsive device controlled in accordance with the changes produced in said circuit, automatic means for causing a started switching device to P complete two revolutions, and means for making the circuit changes produced during the second revolution of said device inefi'ective.

14:. In combination, an electrical circuit, a rotatable switching device normally at rest, means operable in any position of said switching device for associating it with said circuit, means operable during each complete rotation of said switching device for producing a certain number of changes in the associated electrical circuit, a responsive device controlled in accordance with the changes produced in said circuit, automatic means for causing a started switching device to complete two revolutions, and means for rendering effective only circuit changes equal in number to the changes produced during one revolution of said switching device.

15. In combination, an electrical circuit, a rotatable switching device normally at rest, means operable in any position of said device for associating it with said circuit, means operable during each complete rotation of said switching device for producing changes of a certain character in said electrical circuit, a responsive device controlled in accordance with the changes produced in said circuit, automatic means for causing a started switching device to complete a plurality of revolutions, means for disconnecting said device from said circuit only after the completion of said plurality of.

revolutions, and means for making effective only circuit changes equivalent in character to the changes produced during one complete rotation of said device.

16. In combination, an electrical circuit, three signals individual thereto, a relay controlling at its front contacts the circuits of the first and second of said signals, and at its back contact the circuit of the third signal, another relay controlling at its front contact the circuit of said third signal and the circuit of the second signal, and at its back contact the circuit of the first signal, a third relay controlling at its back contact the circuit of said first mentioned relay, and at is front contact the circuit of said second mentioned relay, a switching device for controlling said electrical circuit, means controlled by said switching device for producing at varying intervals changes in said circuit, means responsive to said changes in said circuit for operating said first and sec ond mentioned relays, and means depending on the time interval elapsing between two changes for controlling the operation of said third mentioned relay.

In witness whereof, I hereunto subscribe my name this 4th day of October, A. D.-

ALBEN E. LUNDELL.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. O. 

